\begin{tikzpicture}
    \tkzDefPoints{0/0/O, 1.1/0/R, 3/0/P}
    \tkzDrawCircle[thick](O,R)
    \tkzLabelPoints[left](O)
    \tkzLabelPoints[below=.2em, xshift=.3em](P)

    % 1
    \tkzDrawSegment(O,P)

    % 2
    \tkzDefMidPoint(O,P)  \tkzGetPoint{C}
    \tkzDrawCircle[thick](C,O)
    \tkzDrawPoint(C)
    \tkzInterCC(O,R)(C,O)  \tkzGetPoints{A}{B}
    \tkzLabelPoints[above, xshift=-.2em](A)
    \tkzLabelPoints[below, xshift=-.2em](B)
    \tkzLabelPoints[below](C)

    % 3
    \tkzDrawLines[add=0.2 and 0.2](P,A  P,B)
    \tkzDrawSegments[dashed](O,A  O,B)
\end{tikzpicture}

